109: To attack that darkness once again with Dr. Hunt<p>Dr. Cindy Hunt returns to the show to talk about the upcoming 100th anniversary of the 100 inch Hooker Telescope on Mount Wilson. She explains why this telescope looks like a battleship and tells us how it “completely upended our understanding of the universe”. Also: poetry!</p>Listen:

108: End of mission blues with Dr. Storrie-Lombardi<p>Dr. Lisa Storrie-Lombardi returns to the show to discuss NuSTAR, Spitzer, and what it feels like to end a mission you’ve been working on for decades. Cassini’s Grand Finale has us reflecting on the upcoming demise of the Spitzer Space Telescope.</p>Listen:

107: Loose rocks and soft bots with Dr. McMahon<p>Professor Jay McMahon stops by the show to explain the YORP effect and how it changes asteroid spins and shapes. He also describes his NASA Institute for Advanced Concepts (NIAC) project that is investigating the use of soft robots to explore rubble-pile asteroids.</p>Listen:

106: Sample the mantle with Dr. Peterson<p>Dr. Mary Peterson tells us about basaltic glasses from the Galápagos Islands, and why they might have originated deep within the Earth’s mantle. She also describes her lab work, which involves cool lab coats, security badges, and meticulous sorting of samples.</p>Listen:

105: Tectonic fabric with Dr. Donnellan<p>Dr. Andrea Donnellan stops by the show to talk about GeoGateway, a website that combines different datasets to help geologists. She explains how rocks move like silly putty, and recounts the time a lone cloud masqueraded as tectonic motion.<br /> <br /> Bonus music at the end is “Glorious Dawn” by Colorpulse. Hear more rad science tunes at www.symphonyofscience.com.</p>Listen:

104: Occultation vacation with Dr. Kramer<p>Dr. Emily Kramer stops by the show to try some tea and talk about her trip to South Africa to observe the next New Horizons target, 2014 MU69. She was one of several astronomers and planetary scientists who flew to other countries to watch this object pass in front of a star in the hopes of measuring its diameter.</p>Listen:

103: Meteor showers and “broom stars” with Dr. Ye<p>Dr. Quan-Zhi Ye tries an unusual frappuccino and explains how meteor showers are related to comets. He tells the story of how he became interested in comets and asteroids, and fills us in on some of his recent research.</p>Listen:

102: A thrilling tale of discovery with Dr. Christiansen<p>Dr. Jessie Christiansen returns to the show to talk about newly discovered exoplanets! She explains why this planetary system was devilishly difficult to observe with ground-based telescopes, and how one of the planets poses a puzzle.</p>Listen:

101: The best geologist on Mars with Dr. Francis<p>Dr. Raymond Francis talks about a rock-vaporizing laser and the software that controls it. He describes how he and colleagues programmed a computer to make choices like a geologist would, allowing the Curiosity rover to do more science on Mars.</p>Listen:

99: Photons from exoplanets with Dr. Meshkat<p>Dr. Tiffany Meshkat describes direct imaging of exoplanets, which astronomers have used to discover enormous, young planets. She also talks about WFIRST, a mission under development that would be able to find and characterize exoplanets.</p>Listen:

98: A place on Earth as dry as Mars with Dr. Azua-Bustos<p>Dr. Armando Azua-Bustos talks about how he discovered the driest place on Earth— a region in the Atacama Desert not far from where he grew up. He explains how he collects and studies microbial life that live in these extremely dry regions.</p>Listen:

97: If a glacier falls in a fjord… with Dr. Koppes<p>Dr. Michele Koppes stops by to talk about her glacier research on planet Earth. She describes how a melting glacier triggered a staggeringly large landslide in 2015, and how glaciers can match even humans in their ability to transform the landscape.</p>Listen:

96: Vega, dust, and a giant inflatable bumblebee with Dr. Ciardi<p>Dr. David Ciardi talks about Vega, a bright star that’s “been a part of human lore forever.” Dr. Ciardi and his colleagues discovered that Vega has a nearby ring of dust, implying the presence of planets. He also describes an encounter with a giant inflatable bumblebee at Palomar Observatory.</p>Listen:

95: Asteroid hunting software with John Dailey<p>John Dailey explains how he uses his software engineering skills to discover asteroids at IPAC/Caltech. He helps solve problems inherent to working with astronomical data, such as the challenge of reading in and out huge volumes of data from hard drives.</p>Listen:

94: Seven hundred new craters on Mars with Dr. Daubar<p>Dr. Ingrid Daubar stops by to talk about HiRISE, a camera on a Mars-orbiting spacecraft that takes amazing images of the Martian surface. She explains how she uses these images to search for fresh craters, and how you (yes you!) suggest areas of the planet for this camera to image. (Correction to episode: Mars’ atmosphere is 0.6% that of Earth, not 6%)</p>Listen:

93: Companionable Jupiters with Marta Bryan<p>Marta Bryan shares her new results on exoplanets! She explains how she tested a theory of hot jupiter formation, and how she figured out that planet rotation rates are likely set early on in the planet’s lifetime.</p>Listen:

92: When there’s dust there’s planets with Dr. Patel<p>Dr. Rahul Patel describes his search for undiscovered disks of dust around other stars. He explains how looking for fainter and fainter debris disks may bring us closer to discovering a planetary system similar to our own.</p>Listen:

91: Tectonic hazard on Phobos with Dr. Curren<p>Dr. Ivy Curren talks about Mars’ moon Phobos, and how grooves on its surface indicate that the interior may be fractured. This small, mysterious moon is covered in faults, making it a dicey place for future missions to land.</p>Listen:

90: The universe is full of water with Dr. Paladini<p>Dr Roberta Paladini talks about the space-based Herschel Space Observatory, which was the largest infrared telescope ever launched. It looked at the sky in the far infrared, and discovered an abundance of water in star-forming regions.</p>Listen:

89: Underwater Flying Objects with Prof. Thompson<p>Dr. Andy Thompson explains how he uses robotic ocean gliders to learn about our planet. He tells us how ocean water interacts with the atmosphere, and how parcels of water can preserve information about that interaction for thousands of years.</p>Listen:

Bonus episode: I wrote a book!<p>As part of the 2016 TED Fellows class, I got to meet cool people and I got to talk about asteroids. My TED talk is now online on www.TED.com (check it out!) and the companion book, “Asteroid Hunters”, by me, is now available in the US, UK, Canada, Australia, and India. There’s also e-book and audiobook versions. This bonus episode contains an excerpt from “Asteroid Hunters”.</p>Listen:

88: Designing earthquake alarms with Dr. Burkett<p>Dr. Erin Burkett tells us what prairie dog research has to do with an earthquake early alarm system. She also talks about how to motivate people to prepare for earthquakes, and emphasizes the importance of storytelling in science communication.</p>Listen:

87: Visions of interstellar travel with Dr. Hurt<p>Dr. Robert Hurt returns to the show to talk about artistic depictions of interstellar travel. We discuss the images of the seven-planet TRAPPIST-1 system he and Tim Pyle created— images that graced the cover of Nature and the front page of the New York Times. We also talk about Star Trek: The Next Generation, and what that TV show got right (and wrong) about the visuals of cruising through outer space.</p>Listen:

86: Celestial cinematography with Dr. Kasliwal<p>Professor Mansi Kasliwal talks about the GROWTH project, which uses international teamwork to watch astronomical events around the clock. An individual observer is thwarted by sunrise, but together, an international team can continuously monitor supernovae, neutron stars, and asteroids over 24 hours.</p>Listen:

85: Risk, hazard, and threat: the importance of language with Dr. Billings<p>Dr Linda Billings talks about the importance of clear communication across the expert/non-expert boundary. She describes the difference between the words “risk”, “hazard” and “threat,” as applied to near-Earth objects and gives advice to scientists who want to communicate their research accurately.</p>Listen:

84: Saturn’s siren song with Dr. Burton<p>Dr. Marcia Burton stops by the show to talk about radio waves from Saturn, as measured by the Cassini Spacecraft. We listen to some audio clips, and she explains why it is so difficult to measure the length of Saturn’s day.</p>Listen:

83: Why we archive with Dr. Rebull<p>Dr. Luisa Rebull explains why it is vital to archive astronomical images. NASA archives, such as the ones at IPAC, are accessible everyone on Earth at no cost. Luisa also describes how you can take a tour through archived data via the Dustier, Messier, Messier Marathon.</p>Listen:

82: Searching the sky for asteroids with Eric Christensen<p>Eric Christensen, head of the Catalina Sky Survey, talks about how he and his team hunt asteroids and comets. He explains how astronomers can distinguish between individual asteroids and how new upgrades will let the survey discover more asteroids than ever before.</p>Listen:

81: The era of precision astronomy with Dr. Rich<p>Dr Jeff Rich stops by the show to talk about variable stars. Some variable stars change brightness dramatically over several hours, and certain types can be used to measure distances. Jeff also explains what it’s like to propose for, and get, time on the Hubble Space Telescope.</p>Listen:

80: Places where people can have adventures with Br. Consolmagno<p>Brother Guy Consolmagno shares a Coke and talks about the Vatican Observatory, a discovery that got him in trouble with the Voyager team, and why being next to a dairy farm was convenient when he wanted to measure the properties of meteorites.</p>Listen:

79: LIGO’s high quality (factor) fibers with Dr. Robertson<p>Dr. Norna Robertson shares a drink from her home country and talks about a specific part of LIGO. She explains that LIGO’s eighty-pound mirrors are suspended by four, incredibly thin, silica fibers that were developed just for this project.</p>Listen:

76: Mars’ teenage robot with Dr. Fraeman<p>Dr. Abby Fraeman returns to the show to talk about Opportunity, the rover that won’t quit. Along with its sister rover, Spirit, Opportunity has discovered Mars rocks that could have only formed in the presence of water.</p>Listen:

75: Looking for trouble with Eric Rice<p>Eric Rice talks about systems engineering and we drink what turns out to be the most disgusting beverage yet. He talks about what it is like to control a spacecraft, and explains why predicting what can go wrong with a spacecraft is a lot simpler than predicting what can go wrong at a wedding.</p>Listen:

74: Asteroid families with Dr. Masiero<p>Dr. Joe Masiero returns to the podcast to talk about asteroid families, which are groups of asteroids that astronomers think are fragments from ancient collisions. He describes how he identifies these families, and how this work can help us understand how the solar system used to be millions of years ago.</p>Listen:

73: Earthquake early warning systems with Dr. Weiser<p>Dr Debbie Weiser explains the importance of building an early warning system in the US before a major earthquake hits. Even a few seconds warning is enough to stop elevators, pause surgery, and give peace of mind to everyday folks experiencing aftershocks. To support this program, contact the California Governor’s office or your congressional representatives.</p>Listen:

72: Perturbing the Earth with Dr. Weiser<p>Dr. Debbie Weiser talks about human-made earthquakes on my favorite planet, Earth. She explains how seismologists try to distinguish between natural earthquakes and those caused by human activity, and why the earliest seismometers in California were installed by astronomers.</p>Listen:

71: Rovers on an asteroid with Dr. Takir<p>Dr. Driss Takir stops by the show. He explains how he looks for water that’s molecularly bound up in the rocks on asteroids. He also tells us about the Hayabusa-2 mission, which will put rovers on the the surface of asteroid Ryugu.</p>Listen:

70: Every crater tells a story with Dr. Scully<p>Dr Jennifer Scully talks about the geology of Ceres and Vesta, two large asteroids in the main belt that have been visited by NASA’s DAWN mission. She’s talks about the experience of getting to know each and every crater, and why the first images from Ceres surprised some people.</p>Listen:

69: Pinging passing asteroids with Dr. Naidu<p>Dr. Shantanu Naidu tells us about planetary radar. Using large telescopes in California and Puerto Rico, he bounces radio waves off of asteroids and “listens” for the return signal. With this technique, he’s discovered moons on several asteroids.</p>Listen:

68: Building a new instrument with Dr Hosseini<p>Dr. Sona Hosseini talks about spectroscopy, a technique that allows scientists to determine what celestial bodies are made of. She’s developing new spectrometer that will allow her to look at an entire planet, or comet, all at once.</p>Listen:

65: Black holes don’t suck with Dr. Gorjian<p>Dr. Varoujan Gorjian thoroughly debunks a misconception he hates— the idea that black holes suck. Find out what would happen to the Earth if our Sun was suddenly replaced with a black hole of the same mass, and why is is so challenging to send a probe to Mercury.</p>Listen:

64: Hubble’s Tuning Fork with Dr. Seidel<p>Dr. Marja Seidel stops by the show to talk about galaxy evolution. She also talks about a unique outreach effort she co-founded, called Cielo y Tierra, that shares science with remote communities.</p>Listen:

63: Deciphering dark matter with Dr. Benson<p>Dr. Andrew Benson talks about dark matter, the mysterious stuff that makes up most of the mass of the universe. Andrew explains how we can learn about dark matter, even though we don’t yet know what it is.</p>Listen:

61: Catching a photonic breeze with Dr. Betts<p>Dr. Betts talks about LightSail, an exciting mission to test new technology from The Planetary Society. This is a special joint episode with The Orbital Mechanics podcast.</p>Listen:

60: Data you can see, touch, and lick with Dr. Hunt<p>Dr. Cynthia Hunt talks about the Carnegie Observatories’ astronomical glass plate collection. The Carnegie collection includes historic plates that recorded the moments astronomers made groundbreaking discoveries.</p>Listen:

59: Where the universe was discovered with Dr. Mulchaey<p>Director Dr. John Mulchaey stops by the show to talk about the history and future of the Carnegie Observatories; the place “where the universe was discovered”. This episode is the first of a series on current research at Carnegie.</p>Listen:

57: Voyaging to the edge of the Solar System with Suzy Dodd <p>Project Manager Suzy Dodd tells us about the continuing missions of the Voyager spacecraft. These spacecraft are still collecting unique and valuable data, and Suzy explains how engineers hack the spacecraft to extend their lifespan.</p>Listen:

56: Fiction Science with Mika McKinnon<p>Master of Disaster Mika McKinnon talks about how she injected real science into the sci-fi series “Stargate”. We discuss how she balanced accuracy and entertainment, and how she influenced the way scientists were portrayed on that show.</p>Listen:

55: Space is a team effort with Jan Chodas<p>Jan Chodas stops by the show to talk about her experience working on several pioneering NASA missions, including Galileo, Cassini, the Spirit and Opportunity rovers, and Juno. Note: this was recorded before Juno successfully entered into the orbit of Jupiter.</p>Listen:

54: The granite planet with Dr. Economos<p>Professor Rita Economos talks about her research into magma on Earth. She recounts some of the adventures she’s had searching for rocks, and explains why Earth’s volcanoes appear to be unique in the solar system.</p>Listen:

53: How big? How far? How fast? with Dr. Beaton<p>Dr. Rachael Beaton and I try “Grass Jelly Drink” and talk about one of the major fundamental constants of the universe; the Hubble Constant. She explains what it is and why she and her colleagues are trying to measure it better than it ever has been measured before.</p>Listen:

51: When Mars was the “Pink Planet” with Dr. Smith<p>Dr. Issac Smith visits the show to talk about one of Mars’ past ice ages; a time when most of the planet was covered in ice. He talks about how he made this discovery by looking at the layers of ice deposited on the planet’s North pole.</p>Listen:

50: Ganymede and Iapetus with Dr. Singer<p>Returning guest Dr. Kelsi Singer talks about two of the icy moons of our solar system, Ganymede and Iapetus. She talks about the types of craters we see on their surfaces, and what they can teach us about the moons themselves.</p>Listen:

49: Every known object in the Solar System with Jon Giorgini <p>Jon talks about JPL’s Horizons, an amazing, publicly available system that keeps track of every known object in the solar system. Planets, moons, asteroids, spacecraft, you name it: over 715,000 in total. We discuss how this system is used by engineers, scientists, lawyers, art fans, and marine biologists.</p>Listen:

48: Threading an asteroid through the eye of a keyhole with Dr. Chodas<p>This week’s guest is Dr Paul Chodas, who directs JPL’s Center for Near-Earth Object Studies. He explains how predicting where an asteroid is going can get complicated when the asteroid gets close to a planet. He also talks about an app that lets you explore how a hypothetical asteroid could be deflected.</p>Listen:

47: Punching an asteroid with Dr. Walsh<p>Dr. Kevin Walsh visits the show to talk about a new NASA mission that will launch later this year: OSIRIS REx! This spacecraft will visit an asteroid, grab a bit of surface material, and return the material to Earth for further study. Dr. Walsh talks about the mission and explains how you can help scientists pick the best place on the asteroid for the spacecraft to grab a sample.</p>Listen:

46: Spacecraft no bigger than a breadbox with Dr. Asphaug<p>Professor Erik Asphaug stops by the show to discuss AOSAT-1, a tiny spacecraft that will contain experiments to study the surface of asteroids. AOSAT-1 will rotate once every minute, creating a force inside that exactly mimics gravity on an asteroid. We discuss how AOSAT-1, a cubesat, is being designed and built, and how it may launched from the space station in a “cubesat cannon”.</p>Listen:

45: A glimpse of the Pluto system with Dr. Ennico Smith<p>Dr. Kimberly Ennico Smith, New Horizons deputy project scientist, stops by the show to talk about the new data currently being transmitted to Earth, what it’s like to work on this mission, and the violent past of Pluto’s moon Charon.</p>Listen:

44: Atmospheres in our solar system with Dr. Soto<p>Dr. Alejandro Soto visits the show to talk about the different atmospheres found on planets and moons in our solar system. We talk about wind on Mars, the opening scene of The Martian, Pluto’s thin atmosphere, and what it is like on Saturn’s moon Titan.</p>Listen:

43: The Ice Giants with Dr. Soderlund<p>Dr. Krista Soderlund talks about the ice giants, Uranus and Neptune. She tells us about their unusual rings and moons, and how studying them can teach us about exoplanets.</p>Listen:

42: Finding exoplanets with Dr. Christiansen<p>Dr. Christiansen stops by the show to talk about exoplanets and the Kepler Space Telescope. We share an Australian beverage and she explains how astronomers look for exoplanets, and how the discovery of “hot Jupiters” was a huge surprise to astronomers.</p>Listen:

41: The last of the “great observatories” with Dr. Storrie-Lombardi<p>Dr. Lisa Storrie-Lombardi talks about the Spitzer Space Telescope. She tells us how Spitzer made the first observation of light from a planet outside our solar system. She also describes how engineers are constantly innovating, letting Spitzer make better and more sensitive observations.</p>Listen:

40: Keeping an eye on asteroids with Dr. Yeomans<p>Dr. Don Yeomans, head of JPL’s Near-Earth Object office until his recent retirement, describes how the field of asteroid discovery has changed over the decades. He recalls when early data indicated that asteroid Apophis had a small chance of hitting the Earth (spoiler alert: today, with more data, we know that Apophis will not hit the Earth).</p>Listen:

39: A day in the life of a Mars rover with Dr. Litchtenberg<p>Dr. Kimberly Litchtenburg explains what it is like to explore Mars with the Curiosity rover. It involves daily discussions with scientists, careful programming, and sometimes, fantastic discoveries, like the discovery of a stream bed that once had enough</p>Listen:

38: Mysterious icy travelers with Dr. Fernández<p>Professor Yan Fernández tells us about several baffling comets, including one comet that has a nearly circular path around the sun. He also talks about comet Hale Bopp, which we’ve got to study now, because it won’t return to our part of the solar system until 7000 AD.</p>Listen:

37: Exploring Pluto with Dr. Singer<p>Dr. Kelsi Singer and I drink an unusual beverage while she shares some of the incredible discoveries that she and the New Horizons team are making. We also discuss a contentious issue— should Pluto be called a planet?</p>Listen:

35: Geology at a distance with Dr. Rivkin<p>Dr Andy Rivkin and I drink gin and tonics, and Andy explains what spectroscopy is and what it can teach us about minerals on asteroids. He also describes what it’s like to use some of the world’s most powerful telescopes.</p>Listen:

34: Keeping track of asteroids with Dr. Sphar<p>Dr. Tim Sphar, CEO of NEO Sciences and former director of the Minor Planet Center, stops by the show to talk about how asteroids are cataloged and monitored. He also talks about his experience the day tiny asteroid 2008 TC3 impacted Earth.</p>Listen:

32: How to build a planet with Dr. Kretke<p>Dr. Katherine Kretke investigates how planets are formed with computer models. Her new research had a surprising result— that pebbles play a key role in forming terrestrial planets like Earth and Mars.</p>Listen:

31: If we could put Mars in a bottle… with Paulo Younse<p>Paulo Younse has spent over 5 years studying hermetic seals for tubes. But these aren’t just any tubes— there the tubes that will travel to Mars and carry rocks back to Earth. He describes the challenges of designing the perfect tubes for this ambitious venture.</p>Listen:

30: Space weathering with Dr. Kaluna<p>Dr. Heather Kaluna talks about space weathering, which changes the surfaces of the moon, asteroids, and Mercury. She studies space weathering in a laboratory, where she can reproduce hundreds of millions of years of weathering in just forty minutes.</p>Listen:

29: Keeping the James Webb Space Telescope cool with Dr. Stone<p>The James Webb Space Telescope is the biggest astronomy project in the world right now. It’s an amazingly complex robot, and some of its sensors need to be kept cool. Dr Kris Stone talks about the cooling system, and how it will be tested during the longest continuous test ever conducted at NASA’s Jet Propulsion Laboratory.</p>Listen:

27: Searching Iceland’s lava fields for life on Mars with Dr. Cable<p>Dr Morgan Cable comes back on the podcast to tell us about how she and a team of scientists searched a fresh lava field in Iceland to look for signs of life. They pretended to see the landscape like a rover would, so that the lessons they learned in Icela</p>Listen:

24: Engineering the Galileo Probe, Pt 2.<p>In part 2, engineers who worked on the Galileo probe discuss what it was like when the probe entered Jupiter's atmosphere. This episode includes a bonus story about Pioneer Venus.</p>Listen:

23: Engineering the Galileo Probe, Pt 1.<p>Celebrating the 20th anniversary of the successful deployment of a probe into Jupiter's atmosphere, this episode is a series of interviews with the engineers who worked on this challenging, historic mission.</p>Listen: